PB2245: POLYCYTHEMIA VERA (PV) AND SECONDARY POLYCYTHEMIA (SP): ARE METABOLIC DIFFERENCES JUST THEORIES?
Authors: Osman Yokus, Dilan Serap Cakmak, Istemi Serin
Journal: HemaSphere (2023)

Topic: 16. Myeloproliferative neoplasms - Clinical Background: Polycythemia vera (PV) is an indolent myeloid neoplasm with a relatively long median survival. Detection of JAK2V617F is highly sensitive in detecting PV and distinguishing it from secondary causes. JAK2 mutation in hematopoietic cells has been shown to increase glycolysis and oxidative phosphorylation, hypoglycemia, and adipose atrophy. The JAK 1/2 inhibitor ruxolitinib used in the treatment by inhibiting mutant JAK2 expression. The clear clinical and real-life effects of JAK2 mutations on metabolic parameters in patients with PV are unknown, although it has been theoretically shown that mutant JAK2 causes adipose atrophy, this data needs to be supported by clinical data. Aims: In our study, it was aimed to reveal the metabolic differences between patients diagnosed with PV and secondary polycythemia (SP) by using the baseline characteristics. Methods: Patients diagnosed with PV and SP who were followed up in Istanbul Training and Research Hospital, Hematology Clinic between January 2010 and January 2021 were included in our study. The World Health Organization 2016 revision was based on the diagnosis of PV. In addition to demographic data such as age and gender, initial height, weight, body mass index (BMI), fasting blood glucose, glycosylated hemoglobin (HbA1c) values and presence of diabetes mellitus (DM) were recorded. All of the PV patients included in the study had the JAKV617 mutation. BMI was calculated by taking patients’ weight, in kilograms (kg), divided by their height, in meters squared (BMI = weight (in kg)/ height2 (in m2)). Patients were grouped according to the BMI ranges defined below. The BMI classification, <25 was recorded as normal and below, 25-30 as overweight, and 30 and above as obese. •Normal weight: <25 kg/m2 •Overweight: 25-30 kg/m2 Obese: 30 kg/m2 and above Results: A total of 189 (61.6%) patients included in the study were diagnosed with PV, while 118 (38.4%) were diagnosed with SP. In the statistical analysis between the two groups in terms of age distribution, the rate of patients above 70 years old was higher in the PV group (19.6%), while the rate of patients 40 years old and below was higher in the SP group (26.3%) (p=0.002). While the rate of males was higher in the SP group (90.7%), the rate of females was higher in the PV group (32.3%) (p<0.001). While the mean age was 57.22±14.07 years old in the PV patient group, it was 49.95±14.5 years old in the CP patient group; The mean age at diagnosis was significantly higher in the PV patient group (p<0.001). Mean height, weight, and BMI measurements at the time of diagnosis were higher in the SP group than in the PV group (p<0.001). In the analysis performed according to BMI distribution, the number of patients with normal BMI and the number of non-obese patients in the PV group were found to be significantly higher than in the SP group (p<0.001). No significant difference was found between the PV and SP patient groups in terms of the presence of DM, fasting blood glucose and HbA1c levels (p>0.05, for all). Summary/Conclusion: In conclusion, in our study, mean height, weight and BMI measurements at the time of diagnosis were statistically significantly higher in the SP group than in the PV group. In the analysis made according to BMI distribution, the number of patients with normal BMI and the number of non-obese patients in the PV group were significantly higher than in the SP group, and obesity was significantly higher in the SP patients. There was no significant difference in the presence of DM, fasting blood glucose at the time of diagnosis, and HbA1c levels. The results of the study will guide new studies in terms of the relationship of JAK mutation with metabolic parameters and its role on PV patients.Keywords: Polycythemia vera